Dear r-help,
I'm having this DF
df <- data.frame(id = 1:6,
xout = c(1234, 2134, 234, 456, 324, 345),
xin= c(NA, 34,67,87,34, NA))
and would like to calculate the fraction (xin_t / xout_t-1)
The result should be:
# NA, 2.76, 3.14, 37.18, 7.46, NA
I am sure there is a solution using zoo... but I don't know how...
Thanks for any help!
Patrick